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That company showed up and did some measurements and came up with 38000 BTU's/ hr heat loss. So a 3 or 3.5 ton system needed.

My electrical utility bill average for Dec to Feb was 1500kw /month this is 170500 btu's day and 12 hours / day ( darkness without solar gain) of usage would be 14208 btu's/hr. There is no way I would need 38000btu's hr.

Maybe he likes to size for -6 'F with an assumed HIGH infiltration rate.
.........................................

One needs to review electric usage by the hour if you wish to establish heat capacity required
based on power usage
and equipment heat output
or one must compensate for Heating Degree Days (HDD) versus Design Temperature.

For here the average daily low for that period 16F and the daily average is 23F. That would make dt HDD 65-16= 49. 49 x 90Days = 4410 HDD
A design of 10 would be Design dT of 60. So 60/49 =1.2 that would be 1500 x 1.2 average or 60 kw /day.

Last night I used 16 kw in 9 hours 10 pm to 7 am with an outside temp of 28 and an inside temperature of 63.

For here the average daily low for that period 16F and the daily average is 23F. That would make dt HDD 65-16= 49. 49 x 90Days = 4410 HDD
A design of 10 would be Design dT of 60. So 60/49 =1.2 that would be 1500 x 1.2 average or 60 kw /day.

Last night I used 16 kw in 9 hours 10 pm to 7 am with an outside temp of 28 and an inside temperature of 63.

Jimmy

So what's the equipment?
Strip ?
or heat pump?

Mfg :
Model:

Designer Dan
It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE
Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

For here the average daily low for that period 16F and the daily average is 23F. That would make dt HDD 65-16= 49. 49 x 90Days = 4410 HDD
A design of 10 would be Design dT of 60. So 60/49 =1.2 that would be 1500 x 1.2 average or 60 kw /day.

Last night I used 16 kw in 9 hours 10 pm to 7 am with an outside temp of 28 and an inside temperature of 63.

Jimmy

WHY is your inside temp dropping to 63?

Where does 1500 come from?

If you wish to Use average all meaningful data is destroyed.

Don't you have your electric usage for the last 50 months or so?
Each month can be correlated to HDD.

Designer Dan
It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE
Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

It's based on an expectation of how cold/hot it normally gets. Not average temperatures.
Also, what he designed your indoor temp makes a big difference also.

Both these numbers have standards based on location, that can be deviated.

All this crazy math stuff is why we make the little bucks, and you should listen to the professionals that come out to your home.

I personally think you already have decided what you want in your house.
Your just looking for someone whos going to agree with you.

I have done a load calculation so I should have an idea what is required. He didn't put in insulation values. He did put in running wall length and window sizes. I have a vaulted ceiling that is triangular on top. He put in total height for that wall of 21 ft and he should have used 15.5 ft He didn't know what manual J was, He said he puts the numbers in the program and it gives a recomendation . It may be a manual J program. I don't know. The guy designing the Duckwork did not know what Manual D was. He had a slide card giving him pressure loss for pipe size and length.

The equipment sizing was based on heating load required, from what I gather is wrong according to the experts.

Sorry no secret

Originally Posted by dan sw fl

With EACH of the 24 months data being Kept a Secret, NO ONE CAN DO A REAL LOAD CALC based on Actual Usage.

Here are the numbers:

The estimated values are from when they can't read the meter if the road or drivway is not yet plowed after a heavy snowfall and this happens a few times during the winter as we are located in a remote area and sometimes the road is not plowed right away.